EP1105942B1 - Contact device mainly intended for contact between electric components and circuit supports and method for producing said device - Google Patents

Description

The present invention relates to a contacting device, in particular for contacting electrical components in electrical assemblies on circuit boards, such as printed circuit boards, multichip modules (MCM), flexible circuits or the like, and a method for manufacturing a contacting device.

Such a contacting device is already known from EP-A-593 966, and a method for producing a contacting device.

So far come in the manufacture of electrical assemblies for detachable connection of housed and unhoused Components and displays on circuit boards, such as printed circuit boards or the like, so-called pressure connector or Contactors for use, for example are designed as "conductive rubber foils". in this connection it is generally with metallic or carbon particles filled elastomers, creating an electrical Conductivity is generated. There are also special elastic Contacting devices for use, with wire balls are filled as contact elements.

However, all known contacting devices have the disadvantage that that they sometimes require extremely high contact forces, to ensure a reasonably good contact. Furthermore, the known devices have relative high contact and internal resistance. After all, can with the known devices a contacting of components in depressions of the circuit carriers, such as, for example present on surfaces provided with solder resist are insufficiently realized.

Based on the known prior art, the present Invention the object of a contacting device to provide, in which the disadvantages mentioned be avoided. In particular, a contacting device be provided with a safe, inexpensive and very precise contacting of electrical components on circuit carriers is possible. Furthermore should a suitable method for producing a contacting device to be provided.

The object is achieved according to a first aspect of the invention by a contacting device, in particular for contacting of electrical components on circuit carriers according to claim 1, solved.

The elastic contacting device according to the invention draws First of all, the fact that a high level of contact security is guaranteed. At the same time, the necessary Contact forces are kept relatively low. This leads to a reduction in the risk of damage to the Components and the contacting device. Furthermore, the Contacting device with the appropriate design and layout the components to be contacted are adapted. she is elastic, can even the smallest connection grid and contact areas operate and is inexpensive to manufacture in large quantities. In addition, there is a targeted contact the respective contact points on the components and circuit boards possible.

The contacting device can be almost independent of size in modern PCB and MCM manufacturing are manufactured, because it has a similar structure.

The contacting device in particular provides a detachable electrical connection of components and circuit boards which allows individual components to be replaced or can be replaced.

The connections within the elastic electrical pressure connector can for example by means of the so-called "Micro-via technology", for example by laser structuring or the like, getting produced.

The way in which the individual connections are designed inside the elastic electrical pressure connector, a possible link between the connections as well as the connection of the connections with the individual contact points can be made depending on the application and need become. Individual examples, which are purely exemplary Are natural and are not to be understood exclusively, are described in greater detail below.

Preferred embodiments of the contacting device according to the invention result from the related subclaims.

According to the invention, the elastic dielectric can be made of silicone rubber or be formed polyurethane. Of course it is Invention does not apply to the use of these two materials limited. Rather, any material can be used that on the one hand elastic, and on the other hand electrically insulating is.

In a further embodiment, the contact points can each the level of the top and bottom of the electrical pressure connector overtop. On the one hand, this allows differences in levels in the surfaces of the to be contacted Components, circuit boards and the like in simple Balance way. In addition, reliable and a safe way of contacting wells in the Components and circuit carriers are made, what with the previously known contacting devices are insufficient was possible.

The surfaces of the contact points can advantageously be one Have a metal coating, preferably a gold coating. Thereby contact security is further increased. Naturally other metals are also conceivable as a coating.

According to the invention, individual contact points, each on the top and bottom of the electrical pressure connector are arranged over the connections with each other be connected. In a preferred embodiment are each those contact points that are directly opposite each other Positions on the top and bottom of the electrical Pressure connector are arranged over the connections connected with each other. Depending on the need and application But it can also make sense to offset each other contact points on the top and bottom to connect with each other via the connections. The present Invention is based on no special interconnection of the individual Contact points on the top and bottom of the electrical pressure connector limited. Rather results the necessary interconnection from the to be operated Connection grids and contact surfaces of the to be contacted Components.

In a further embodiment, individual contact points that on the top and / or bottom of the electrical Pressure connector are arranged side by side, over the connections must be connected. This allows even the smallest connection grid and contact areas are even easier the components are operated.

The connections in the electrical pressure connector can be advantageous form a three-dimensional circuit system. Thereby the so-called "translator effect" can also be used if necessary. Such a "translator effect" is particularly required if the contact to be made Component has a very fine connection grid, while the circuit carrier has a coarser grid. The three-dimensional circuit system allows the Further increase contact security. In addition, a and the same contacting device is also universal for contacting of different components can be used.

The three-dimensional circuit system can preferably have a meandering shape exhibit.

In a further embodiment, at least some of the connections in releasable contact with other connections in the electrical pressure connector can be arranged. This can linking the electrically conductive connections within of the elastic electrical pressure connector depending on prevailing contact force vary. That means that inside of the electrical pressure connector different Structures of the three-dimensional circuit system generated can be. This is a variation in the connection of individual contact points possible, which increases flexibility when contacting different components, as well as contact security is further increased.

According to the electrical pressure connector from a or more layers of an elastic dielectric be educated. Depending on your needs, you can use thicker or thinner ones Contacting devices are created, making larger Level differences between the individual components and circuit carriers can be better balanced.

The circuit board points to the Top and / or bottom of an electrically conductive Layer, preferably a metal layer. A preferred one Metal is copper, but there are also other metals conceivable that are suitable as electrical conductors. Farther the layer can also be made of other electrically conductive Materials and compositions are made. As an an example this includes silver conductive adhesive.

When using two or more dielectric layers this one on the top and / or the bottom electrically conductive layer, preferably a metal layer, exhibit. Here, too, is the use of the above Materials conceivable and possible.

The electrically conductive layer can preferably be formed as a film his. However, you can also by screen printing, a special paint or the like can be formed.

In a further embodiment, on the top and / or the bottom of the electrical pressure connector or several layers of a photo film can be provided.

According to the invention, the connections in the electrical Pressure connectors are arranged via a structuring the dielectric layer (s), if present the electrical one conductive layer (s) and, if available, the photo film (s) be trained. Thus the connections can, for example using "micro-via technology", for example using laser structuring, similar to the production of modern circuit boards, getting produced. This allows the invention Contacting device manufactured in a particularly cost-effective manner become.

According to the invention, the contact points and / or the metal layer (s) be galvanically molded. Furthermore can also the connections within the electrical pressure connector be generated galvanically. Instead of galvanic generation the elements mentioned are also other types of production, such as conductive paste printing or the like, possible.

Through the contacting device according to the invention, electrical Connected components in a simple and safe manner become. The required contact force as well as the required The contact path of the individual contact points can be via the elasticity of the dielectric and the design of the circuit system consisting of the connections - and thereby for example by the number of available translator layers adjusted and to the prevailing circumstances be adjusted.

The contacting device can also be used as a BGA (ball grid array) or micro-BGA, which is inexpensive Assembly of cheap products and products with large volume allows.

According to a second aspect of the present invention a method according to claim 9 for producing a contacting device, preferably for contacting electrical components on circuit carriers, in particular for producing a like The contacting device according to the invention described above provided.

The method according to the invention can be used in a simple manner and inexpensive way the contacting devices described above produce. The advantages, effects, Effects and the functioning of the process is based on the The above statements on the contacting device in full Referenced and hereby referred.

The production of the electrical pressure connector can, for example by coating an electrically conductive Layer, such as a metal layer and here in particular one Copper layer, with a liquid dielectric material. The coating can be done by casting (as with solder mask), Spraying, spinning, rolling or similar processes respectively. Also laminating partially polymerized Dielectric foils are possible. Then it turns on the dielectric material on that of the first metal layer opposite side applied a second metal layer and the dielectric cured. Then the structuring of connections are made.

Preferred embodiments of the method according to the invention result from the related subclaims.

According to the invention, two or more layers of an elastic Dielectric are made on the top and / or underside with an electrically conductive layer be coated. The individual layers of the dielectric are used to manufacture the electrical Pressure connector connected together.

As a result, thicker contacting devices can also be created be especially when compensating for larger level differences of the individual components are advantageous. The The number of layers required depends on the need and use case.

In a further embodiment, the top and / or the bottom can the dielectric layer (s) with at least one Photo film can be coated. The number of to use Layers of photo film result depending on the need. The photo film (s) can protect the underlying components serve. It can also be used to structure the individual connections be used.

The structuring of the dielectric layer (s) can advantageously and / or the electrically conductive layer (s) and / or the photo film (s) by laser structuring - for example by means of laser drilling and / or by photo structuring and / or by etching structuring. Indeed other types of structuring are also conceivable.

According to the contact points can be galvanically on the Top and bottom of the circuit board can be built. But there are also the others as described above Generation types conceivable.

The contact points can advantageously be provided with a metal layer, for example, a gold layer.

In a further embodiment, the individual dielectric layers over the metal layer (s) to form the electrical Pressure connector can be contacted.

Fig.1 eine Anordnung eines elektrischen Bauelements und eines Schaltungsträgers, die über eine erfindungsgemäße Kontaktiervorrichtung aneinander ankontaktiert sind;

Fig.2 eine weitere Ausführungsform der erfindungsgemäßen Kontaktiervorrichtung;

Fig.3 eine andere Ausführungsform der erfindungsgemäßen Kontaktiervorrichtung in ihrer Ausgangshöhe vor dem Ankontaktieren; und

Fig.4 eine Kontaktiervorrichtung gemäß Fig.3 in ihrer Kontaktierhöhe nach dem Ankontaktieren.

The invention will now be explained in more detail using exemplary embodiments with reference to the accompanying drawing. It shows:

1 shows an arrangement of an electrical component and a circuit carrier, which are contacted to one another via a contacting device according to the invention;

2 shows a further embodiment of the contacting device according to the invention;

3 shows another embodiment of the contacting device according to the invention in its initial height before contacting; and

4 shows a contacting device according to FIG. 3 in its contacting height after contacting.

1 shows a printed circuit board 10 which has a Contacting device 20 on an electrical component 11 is contacted. To generate sufficient contact force are 20 holding elements on both sides of the contacting device 12 provided.

Both the printed circuit board 10 and the electrical component 11 have a contact grid with a large number of contacts 13 on. The individual contacts 13 are via the contacting device 20 connected together.

For this purpose, the contacting device 20 has an electrical one Pressure connector 21, which is an elastic dielectric having. Furthermore, the electrical pressure connector 21 a number of electrically conductive connections 22. The Connections 22 each connect a number of contact points 25 on top 23 and bottom 24 of the electrical pressure connector 21 are arranged. The Contact points 25 are each with the contacts 13 of the circuit board 10 and the electrical component 11 in connection, whereby the releasable contacting of the component 11 on the circuit board 10 is made possible. The contact points 25 protrude the plane of the top 23 and bottom 24, thereby also a contact in the corresponding deepenings electrical components 10, 11 is possible.

2 shows another embodiment of the contacting device 20 shown. Like the one shown in Fig.1 Such contact points are also embodiments in FIG 25 interconnected via connections 22 that directly opposite on the top 23 and the bottom 24 of the electrical pressure connector 21 are arranged. in the In contrast to FIG. 1, the connections 22 are different trained so that within the electrical pressure connector 21 another, formed by the connections 22 three-dimensional circuit system results. The design which circuit systems are suitable depends on according to the application.

3 and 4 is yet another embodiment of a contacting device 20 according to the invention.

3 shows the contacting device 20 before the actual one Contacting process with an initial height "ha". The electric one Pressure connector 21 has several layers of an elastic Dielectric on. The individual dielectric layers are with on their top and bottom a metal layer 27 coated. Besides, the whole electrical pressure connector 21 on its top 23 and its underside 24 is coated with a metal layer 26.

Furthermore, on the top 23 and bottom 24 of the electrical pressure connector 21 a plurality of contact points 25 provided. The individual metal layers 26 and 27 and the dielectric layers are structured and form a three - dimensional circuit system, which consists of the individual connections 22 exists. About that from the connections 22 formed circuit system are both such contact points 25 on the opposite top 23 and underside 24 of the electrical pressure connector 21 are arranged, as well as such contact points 25 with each other connected, either on the top 23 or the bottom 24 are arranged side by side. resultant creates a contact device that is universal for different components with different connection grids and contact surfaces are formed. Through the special design of the three-dimensional circuit system the so-called "translator effect" can be generated, whereby components and contacting devices with different Gridings of the contact points nevertheless satisfactory can be contacted to each other.

After contacting and applying a suitable one Contact force is the contacting device 20 in the Contact height "he" compressed, as shown in Fig.4 is. By squeezing the electrical pressure connector 21 become the three-dimensional circuit system forming compounds 22 shifted. It results a three-dimensional circuit system in which in the state the contact directly opposite each other Contact points 25 on the top 23 and the bottom 24 of the electrical pressure connector 21 via the Connections 22 are electrically connected to one another.

With a lower contact force or with a contact force that across the entire width of the contacting device is strongly trained, at least in Areas of the electrical pressure connector 21 Generate circuit system in which also neighboring or to each other staggered contact points 25 over the connections 22 are interconnected. This allows the structure of the electrical through the connections 22 Pressure connector 21 formed three-dimensional circuit system about the elasticity of the dielectric - and thus the electrical pressure connector 21-, and about the strength of the adjust the contact force as required and if necessary change.

The following is an example of a manufacturing process described a contacting device according to the invention. First, a thin copper foil 26 with liquid silicone rubber or polyurethane coated as a dielectric. This coating can be done by casting (as with solder mask), Spraying, spinning, rolling or the like. Then a second copper foil 27 is on the laminated still liquid dielectric. Alternatively, you can also a copper layer on top of the already hardened dielectric be applied. Then the elastic Dielectric hardened. After that, connections 22 - also Called micro vias - in the copper foils 26, 27 and the dielectric by means of laser structuring, for example by Laser drilling to create a first via level brought in. In addition, the metal layers still be photo or etched.

Depending on requirements, thicker contacting devices can be produced 20 the process steps described so far can be repeated several times. An electrical pressure connector is created 21 with the structure shown in Fig.3. After the dielectric layers have hardened, the last one applied dielectric layer, that is, the outside lying dielectric layer, with one or more layers Photo film coated. The photo foils and, depending on your needs, the Dielectric layers are used to form connections 22 lasersrtukturiert. Subsequently, 23 and the underside 24 of the electrical pressure connector 21 Contacts applied galvanically and gold-plated. Then one or more photo films are placed on top 23 and the underside 24 of the electrical pressure connector 21 applied. On the one hand, these photo films serve as protection for the contacts, and on the other hand as starting material for the subsequent generation of the contact points 25.

Now the photo films for creating the contact points 25 laser-structured. Then the contact points 25 galvanically built on the contacts and then galvanically gilded. The photo films are stripped and then a final etching structuring of the upper side 23 and the bottom 24 made. The resulting contacting device 20 can be used to connect different electrical components are used.

Claims (13)

1. Contact-making device for making electrical contacts between components, with a zero-insertion-force connector (21), which has an elastic dielectric, with contact points (25) on an upper side (23) and an underside (24) of the zero-insertion-force connector (21) and with electrically conducting connections (22) which respectively connect a number of these contact points (25) to one another, characterized in that the elastic dielectric is present in at least one layer, at least one layer of the dielectric is provided on an upper side or an underside with a structured metal layer (26, 27) and the connections (22) connect the metal layer (26, '27) to contact points (25) on the oppositely lying underside or upper side of the layer of the dielectric.
2. Contact-making device according to Claim 1, in which at least one layer of the dielectric is provided on the upper side and/or the underside with a structured metal layer (26, 27) and the connections (22) connect the metal layers (26, 27) to one another.
3. Contact-making device according to Claim 1 or 2, in which at least two layers of the dielectric are present, a metal layer (26, 27) is arranged between two layers of the dielectric and the connections (22) connect contact points (25) which are offset laterally in relation to one another with respect to the layers to one another via the metal layer (26, 27).
4. Contact-making device according to one of Claims 1 to 3, in which all the upper sides and undersides of the layers of the dielectric are provided with a respective structured metal layer (26, 27) and the connections (22) in each case connect two metal layers to each other.
5. Contact-making device according to one of Claims 1 to 4, in which there are contact points (25) which are arranged next to one another on the same upper side (23) or underside (24) of the zero-insertion-force connector (21) and are connected to one another via the connections (22).
6. Contact-making device according to one of Claims 1 to 5, in which the elastic dielectric is formed from silicone rubber or polyurethane.
7. Contact-making device according to one of Claims 1 to 6, in which the surfaces of the contact points (25) have a gold coating.
8. Contact-making device according to one of Claims 1 to 7, in which at least some of the connections (22) are arranged in releasable contact with respect to other connections (22) in the zero-insertion-force connector (21).
9. Process for producing a contact-making device for. making electrical contacts between components, in which, in a first step, a layer of an elastic dielectric is provided on at least one upper side or underside with a metal layer (26, 27), in a second step, the dielectric is structured and, in a third step, a number of electrically conducting connections (22) are established through the dielectric, by which connections a number of contact points (25) on the upper side and underside are connected to one another.
10. Process according to Claim 9, in which, in the first step, a metal layer (26, 27) is in each case applied to the upper side and the underside of the layer of the dielectric.
11. Process according to Claim 9 or 10, in which at least one further layer of the dielectric is structured and provided with electrically conducting connections and the layers of the dielectric are connected to one another in such a way that contact points (25) on the upper side of the uppermost layer are connected in an electrically conducting manner to contact points (25) on the underside of the lowermost layer.
12. Process according to Claim 11, in which the layers of the dielectric are provided on both sides with a metal layer (26, 27) and the layers are connected to one another by contacts being electrolytically made between the metal layers.
13. Process according to one of Claims 9 to 12, in which the electrically conducting connections (22) are produced as micro-vias.

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